ok I asked if it would be ok to use sand for phlogius or Phlogiellus sp's on The Australian Tarantula Association Forum and this is the answer I got from Brendan stent the guy who discovered the Stents Birdeater.
Brendan :"I do not see why not, I have collected Stent's Birdeater from very sandy river banks not far from the coast. If the sand is well washed and they have somewhere to hide there should be no problem......"
and I also noticed he keeps his pseudocrassipes as well as his Stents Birdeaters on sand to, so I guess you can keep phlogius or Phlogiellus sp's on sand....